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Longwood Compensation Reservoir (information from Ken Heywood)

The compensation reservoir was built around 1840 at the start of the Corporations act when the main reservoirs were built by people who had to prove a worth of £10K - one of the first corporations in the country.

Because water was taken from natural sources to fill the reservoirs the compensation reservoir was to compensate the mill owners for water loss and exempt them payment for the other water through the rates system.

Two other interesting points I discovered when looking into this is that the owners of the reservoirs and the compensated mill owners were usually the same people!!! and the reservoirs look 'newer' because the top one was re-faced in the 1930s